The present invention relates to a telecommunications system which includes telecommunications networks operating in conjunction with a wide area internetwork, such as the Internet, and more particularly relates to providing telephone services through such an internetwork including directory assistance for internetwork telephone calls.
The written description. uses a large number of acronyms to refer to various services, messages and system components. Although generally known, use of several of these acronyms is not strictly standardized in the art. For purposes of this discussion, acronyms therefore will be defined as follows:
Advanced Intelligent Network (AIN)
Central Control Unit (CPU)
Central Office (CO)
Central Office Code (NNX)
Common Channel Signaling (CCS)
Common Channel Interoffice Signaling (CCIS)
Customer Premises Equipment (CPE)
Destination Point Code (DPC)
Domain Name Service (DNS)
Dual Tone Multifrequency (DTMF)
Dynamic Host Configuration Protocol (DHCP)
Integrated Service Control Point (ISCP)
Integrated Services Digital Network (ISDN)
ISDN User Part (ISDN-UP),
International Standards Organization (ISO)
Internet Protocol (IP)
Internet Telephony Server (ITS)
Line Information Database (LIDB)
Local Access and Transport Area (LATA)
Local Area Network (LAN)
Master Control Unit (MCU)
Message Signaling Unit (MSU)
Message Transfer Part (MTP)
Open Systems Interconnection (OSI)
Operator Service System (OSS)
Origination Point Code (OPC)
Plain Old Telephone Service (POTS)
Point in Call (PIC)
Point in Routing (PIR)
Point of Presence (POP)
Public Switch Telephone Network (PSTN)
Recent Change (RC)
Routing and Administration Server (RAS)
Service Control Point (SCP)
Service or Switching Point (SSP)
Signaling System 7 (SS7)
Signaling Point (SP)
Signaling Transfer Point (STP)
Transaction Capabilities Applications Protocol (TCAP)
Transmission Control Protocol (TCP)
The xe2x80x9cInternetxe2x80x9d is a collection of networks, including Arpanet, NSFnet, regional networks such as NYsernet, local networks at a number of university and research institutions, and a number of military networks. The protocols generally referred to as TCP/IP were originally developed for use only through Arpanet and have subsequently become widely used in the industry. The protocols provide a set of services that permit users to communicate with each other across the entire Internet. The specific services that these protocols provide are not important to the present invention, but include file transfer, remote log-in, remote execution, remote printing, computer mail, and access to network file systems.
The basic function of the Transmission. Control Protocol (TCP) is to make sure that commands and messages from an application protocol, such as computer mail, are sent to their desired destinations. TCP keeps track of what is sent, and retransmits anything that does not get to its destination correctly. If any message is too long to be sent as one xe2x80x9cdatagram,xe2x80x9d TCP will split it into multiple datagrams and makes sure that they all arrive correctly and are reassembled for the application program at the receiving end. Since these functions are needed for many applications, they are collected into a separate protocol (TCP) rather than being part of each application. TCP is implemented in the transport layer of the OSI reference model.
The Internet Protocol (IP) is implemented in the network layer of the OSI reference model, and provides a basic service to TCP: delivering datagrams to their destinations. TCP simply hands IP a datagram with an intended destination; IP is unaware of any relationship between successive datagrams, and merely handles routing of each datagram to its destination. If the destination is a station connected to a different LAN, the IP makes use of routers to forward the message.
In simplified fashion the Internet may be viewed as a series of routers connected together with computers connected to the routers. In the addressing scheme of the Internet an address comprises four numbers separated by dots. An example would be 164.109.211.237. Each machine on the Internet has a unique number which constitutes one of these four numbers. In the address the leftmost number is the highest number. By analogy this would correspond to the ZIP code in a mailing address. At times the first two numbers constitute this portion of the address indicating a network or a locale. That network is connected to the last router in the transport path. In differentiating between two computers in the same destination network only the last number field changes. In such an example the next number field 211 identifies the destination router. When the packet bearing the destination address leaves the source router it examines the first two numbers in a matrix table to determine how many hops are the minimum to get to the destination. It then sends the packet to the next router as determined from that table and the procedure is repeated. Each router has a database table that finds the information automatically. This continues until the packet arrives at the destination computer. The separate packets that constitute a message may not travel the same path depending on traffic load. However they all reach the same destination and are assembled in their original order in a connectionless fashion. This is in contrast to connection oriented modes such as frame relay and ATM or voice.
One or more companies have recently developed software for use on personal computers to permit two-way transfer of real-time voice information via an Internet data link between two personal computers. In one of the directions, the sending computer converts voice signals from analog to digital format. The software facilitates data compression down to a rate compatible with modem communication via a POTS telephone line. The software also facilitates encapsulation of the digitized and compressed voice data into the TCP/IP protocol, with appropriate addressing to permit communication via the Internet. At the receiving end, the computer and software reverse the process to recover the analog voice information for presentation to the other party. Such programs permit telephone-like communication between Internet users registered with Internet Phone Servers.
The book xe2x80x9cMastering the Internetxe2x80x9d, Glee Cady and Pat McGregor, SYBEX Inc., Alameda, Calif., 1994, ISBN 94-69309, very briefly describes three proprietary programs said to provide real-time video and voice communications via the Internet.
Palmer et al. U.S. Pat. No. 5,375,068, issued Dec. 20, 1994 for Video Teleconferencing for Networked Workstations discloses a video teleconferencing system for networked workstations. A master process executing on a local processor formats and transmits digital packetized voice and video data, over a digital network using TCP/IP protocol, to remote terminals.
Lewen et al. U.S. Pat. No. 5,341,374, issued Aug. 23, 1994 for Communication Network Integrating Voice Data and Video with Distributed Call Processing, discloses a local area network with distributed call processing for voice, data and video. Real-time voice packets are transmitted over the network, for example to and from a PBX or central office.
Hemmady et al. U.S. Pat. No. 4,958,341, issued Sep. 18, 1990 for Integrated Packetized Voice and Data Switching System, discloses an integrated packetized voice and data switching system for a metropolitan area network (MAN). Voice signals are converted into packets and transmitted on the network. Tung et al. U.S. Pat. Nos. 5,434,913, issued Jul. 18, 1995, and 5,490,247, issued Feb. 6, 1996, for Video Subsystem for Computer Based Conferencing System, disclose an audio subsystem for computer-based conferencing. The system involves local audio compression and transmission of information over an ISDN network.
Hemmady et al. U.S. Pat. No. 4,872,160, issued Oct. 3, 1989, for Integrated Packetized Voice and Data Switching System, discloses an integrated packetized voice and data switching system for metropolitan area networks.
Sampat et al. U.S. Pat. No. 5,493,568, issued Feb. 20, 1996, for Media Dependent Module Interface for Computer Based Conferencing System, discloses a media dependent module interface for computer based conferencing system. An interface connects the upper-level data link manager with the communications driver.
Koltzbach et al. U.S. Pat. No. 5,410,754, issued Apr. 25, 1995, for Bi-Directional Wire Line to Local Area Network Interface and Method, discloses a bi-directional wire-line to local area network interface. The system incorporates means for packet switching and for using the internet protocol (IP).
It is an object of the present invention to provide telephone service via the Internet to users of the public telecommunications network without a need for such customers to have computer access or computer literacy.
It is a further object of the invention to provide such telephone service in a seamless and transparent fashion including special telephone services and particularly providing directory assistance.
It another object of the invention to provide with such Internet telephone services directory assisted call completion.
It a further object of the invention to provide such Internet telephone services directory assisted call completion using for the most part hardware and plant which presently exists in public switched telecommunications systems and in the Internet.
A public switched telephone network utilizing program controlled switching systems controlled by common channel interoffice signaling (CCIS) and preferably an advanced intelligent network (AIN) CCIS network is arranged in an architecture to provide a methodology for facilitating telephone use of the Internet by customers on an impromptu basis. The system permits a caller to set-up and carry out a telephone call over the Internet from telephone station to telephone station without access to computer equipment and without the necessity of maintaining a subscription to any Internet service. Billing may be accomplished on a per call basis. The calls may be inter and intra LATA, region or state or country. It is a particular feature of the invention that directory assistance is offered to callers, with or without call completion at the option of the caller. Such assistance is rendered through the use of procedures presently familiar to the caller from usage of the public switched telephone network. The system utilizes existing common channel signaling facilities along with Internet signaling and voice switching to permit the use of existing public switched telephone network plant for providing the directory assistance and call completion through a new methodology. A centralized directory number database may be provided according to one embodiment of the invention. Alternatively and preferably use is made of existing databases through interconnection or action to permit accessing of multiple databases in a hierarchical manner.